Centre for Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, United Kingdom.
College of Chemical and Biological Engineering & ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310058, China; Research Centre of Biological Computation, Zhejiang Laboratory, Hangzhou 311100, China.
J Mol Biol. 2022 Nov 15;434(21):167829. doi: 10.1016/j.jmb.2022.167829. Epub 2022 Sep 15.
Enterobacteria phage P1 expresses two types of tail fibre, S and S'. Despite the wide usage of phage P1 for transduction, the host range and the receptor for its alternative S' tail fibre was never determined. Here, a ΔS-cin Δpac E. coli P1 lysogenic strain was generated to allow packaging of phagemid DNA into P1 phage having either S or S' tail fibre. P1(S') could transduce phagemid DNA into Shigella flexneri 2a 2457O, Shigella flexneri 5a M90T and Escherichia coli O3 efficiently. Mutational analysis of the O-antigen assembly genes and LPS inhibition assays indicated that P1(S') transduction requires at least one O-antigen unit. E. coli O111:B4 LPS produced a high neutralising effect against P1(S') transduction, indicating that this E. coli strain could be susceptible to P1(S')-mediated transduction. Mutations in the O-antigen modification genes of S. flexneri 2a 2457O and S. flexneri 5a M90T did not cause significant changes to P1(S') transduction efficiency. A higher transduction efficiency of P1(S') improved the delivery of a cas9 antimicrobial phagemid into both S. flexneri 2457O and M90T. These findings provide novel insights into P1 tropism-switching, by identifying the bacterial strains which are susceptible to P1(S')-mediated transduction, as well as demonstrating its potential for delivering a DNA sequence-specific Cas9 antimicrobial into clinically relevant S. flexneri.
肠杆菌噬菌体 P1 表达两种类型的尾部纤维，S 和 S'。尽管噬菌体 P1 被广泛用于转导，但它的替代 S'尾部纤维的宿主范围和受体从未被确定过。在这里，生成了一个 ΔS-cin Δpac E. coli P1 溶源菌株，以允许将噬菌体质粒 DNA 包装到具有 S 或 S'尾部纤维的 P1 噬菌体中。P1(S')可以有效地将噬菌体质粒 DNA 转导到福氏志贺菌 2a 2457O、福氏志贺菌 5a M90T 和大肠杆菌 O3 中。O-抗原组装基因的突变分析和 LPS 抑制实验表明，P1(S')转导需要至少一个 O-抗原单位。大肠杆菌 O111:B4 LPS 对 P1(S')转导产生了很高的中和作用，表明该大肠杆菌菌株可能容易受到 P1(S')介导的转导。福氏志贺菌 2a 2457O 和福氏志贺菌 5a M90T 的 O-抗原修饰基因的突变并没有导致 P1(S')转导效率的显著变化。P1(S')的更高转导效率提高了 cas9 抗菌噬菌体质粒在福氏志贺菌 2457O 和 M90T 中的递送效率。这些发现为 P1 嗜性转换提供了新的见解，确定了易受 P1(S')介导转导的细菌菌株，并展示了其将 DNA 序列特异性 Cas9 抗菌肽递送到临床相关福氏志贺菌中的潜力。
